Quantitative Förster Resonance Energy Transfer: Efficient Light Harvesting for Sequential Photo‐Thermo‐Electric Conversion

Abstract Light is essential to all life on the earth. Thus, highly efficient light‐harvesting systems with the sequential energy transfer process are significant for using solar energy in photosynthesis. For developing an efficient light‐harvesting system, a liquid aggregation‐induced emission (AIE) dye TPE‐EA is obtained, as a donor and solvent, which can light up the aggregation caused quenching (ACQ) Nile Red (NiR, acceptor) to construct a quantitative Förster resonance energy transfer (FRET) system in NiR⊂TPE‐EA. Impressively, this FRET pair shows an impressive photothermal effect, producing a peak temperature of 119 °C while excited by UV light, with 37.8% of conversion efficiency. NiR⊂TPE‐EA is quite different from most other photothermal materials, which require excitation with long wavelength light (>520 nm). Therefore, NiR⊂TPE‐EA firstly converts the solar into thermal energy and then into electric energy to achieve sequential photo‐thermo‐electric conversion. Such sequential conversion, suitable for being excited by sunlight, is anticipated to unlock new and smart approaches for capturing solar energy.